1use language::{
2 Anchor, AnchorRangeExt, BufferSnapshot, Chunk, Edit, Point, PointUtf16, TextSummary, ToOffset,
3};
4use parking_lot::Mutex;
5use std::{
6 cmp::{self, Ordering},
7 iter,
8 ops::{Range, Sub},
9 sync::atomic::{AtomicUsize, Ordering::SeqCst},
10};
11use sum_tree::{Bias, Cursor, FilterCursor, SumTree};
12use theme::SyntaxTheme;
13
14pub trait ToFoldPoint {
15 fn to_fold_point(&self, snapshot: &FoldSnapshot, bias: Bias) -> FoldPoint;
16}
17
18#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
19pub struct FoldPoint(pub super::Point);
20
21impl FoldPoint {
22 pub fn new(row: u32, column: u32) -> Self {
23 Self(super::Point::new(row, column))
24 }
25
26 pub fn row(self) -> u32 {
27 self.0.row
28 }
29
30 pub fn column(self) -> u32 {
31 self.0.column
32 }
33
34 pub fn row_mut(&mut self) -> &mut u32 {
35 &mut self.0.row
36 }
37
38 #[cfg(test)]
39 pub fn column_mut(&mut self) -> &mut u32 {
40 &mut self.0.column
41 }
42
43 pub fn to_buffer_point(&self, snapshot: &FoldSnapshot) -> Point {
44 let mut cursor = snapshot.transforms.cursor::<(FoldPoint, Point)>();
45 cursor.seek(self, Bias::Right, &());
46 let overshoot = self.0 - cursor.start().0 .0;
47 cursor.start().1 + overshoot
48 }
49
50 pub fn to_buffer_offset(&self, snapshot: &FoldSnapshot) -> usize {
51 let mut cursor = snapshot.transforms.cursor::<(FoldPoint, Point)>();
52 cursor.seek(self, Bias::Right, &());
53 let overshoot = self.0 - cursor.start().0 .0;
54 snapshot
55 .buffer_snapshot
56 .to_offset(cursor.start().1 + overshoot)
57 }
58
59 pub fn to_offset(&self, snapshot: &FoldSnapshot) -> FoldOffset {
60 let mut cursor = snapshot
61 .transforms
62 .cursor::<(FoldPoint, TransformSummary)>();
63 cursor.seek(self, Bias::Right, &());
64 let overshoot = self.0 - cursor.start().1.output.lines;
65 let mut offset = cursor.start().1.output.bytes;
66 if !overshoot.is_zero() {
67 let transform = cursor.item().expect("display point out of range");
68 assert!(transform.output_text.is_none());
69 let end_buffer_offset = snapshot
70 .buffer_snapshot
71 .to_offset(cursor.start().1.input.lines + overshoot);
72 offset += end_buffer_offset - cursor.start().1.input.bytes;
73 }
74 FoldOffset(offset)
75 }
76}
77
78impl ToFoldPoint for Point {
79 fn to_fold_point(&self, snapshot: &FoldSnapshot, bias: Bias) -> FoldPoint {
80 let mut cursor = snapshot.transforms.cursor::<(Point, FoldPoint)>();
81 cursor.seek(self, Bias::Right, &());
82 if cursor.item().map_or(false, |t| t.is_fold()) {
83 if bias == Bias::Left || *self == cursor.start().0 {
84 cursor.start().1
85 } else {
86 cursor.end(&()).1
87 }
88 } else {
89 let overshoot = *self - cursor.start().0;
90 FoldPoint(cmp::min(
91 cursor.start().1 .0 + overshoot,
92 cursor.end(&()).1 .0,
93 ))
94 }
95 }
96}
97
98pub struct FoldMapWriter<'a>(&'a mut FoldMap);
99
100impl<'a> FoldMapWriter<'a> {
101 pub fn fold<T: ToOffset>(
102 &mut self,
103 ranges: impl IntoIterator<Item = Range<T>>,
104 ) -> (FoldSnapshot, Vec<FoldEdit>) {
105 let mut edits = Vec::new();
106 let mut folds = Vec::new();
107 let buffer = self.0.buffer.lock().clone();
108 for range in ranges.into_iter() {
109 let range = range.start.to_offset(&buffer)..range.end.to_offset(&buffer);
110 if range.start != range.end {
111 let fold = Fold(buffer.anchor_after(range.start)..buffer.anchor_before(range.end));
112 folds.push(fold);
113 edits.push(text::Edit {
114 old: range.clone(),
115 new: range,
116 });
117 }
118 }
119
120 folds.sort_unstable_by(|a, b| sum_tree::SeekTarget::cmp(a, b, &buffer));
121
122 self.0.folds = {
123 let mut new_tree = SumTree::new();
124 let mut cursor = self.0.folds.cursor::<Fold>();
125 for fold in folds {
126 new_tree.push_tree(cursor.slice(&fold, Bias::Right, &buffer), &buffer);
127 new_tree.push(fold, &buffer);
128 }
129 new_tree.push_tree(cursor.suffix(&buffer), &buffer);
130 new_tree
131 };
132
133 consolidate_buffer_edits(&mut edits);
134 let edits = self.0.sync(buffer.clone(), edits);
135 let snapshot = FoldSnapshot {
136 transforms: self.0.transforms.lock().clone(),
137 folds: self.0.folds.clone(),
138 buffer_snapshot: buffer,
139 version: self.0.version.load(SeqCst),
140 };
141 (snapshot, edits)
142 }
143
144 pub fn unfold<T: ToOffset>(
145 &mut self,
146 ranges: impl IntoIterator<Item = Range<T>>,
147 ) -> (FoldSnapshot, Vec<FoldEdit>) {
148 let mut edits = Vec::new();
149 let mut fold_ixs_to_delete = Vec::new();
150 let buffer = self.0.buffer.lock().clone();
151 for range in ranges.into_iter() {
152 // Remove intersecting folds and add their ranges to edits that are passed to sync.
153 let mut folds_cursor = intersecting_folds(&buffer, &self.0.folds, range, true);
154 while let Some(fold) = folds_cursor.item() {
155 let offset_range = fold.0.start.to_offset(&buffer)..fold.0.end.to_offset(&buffer);
156 edits.push(text::Edit {
157 old: offset_range.clone(),
158 new: offset_range,
159 });
160 fold_ixs_to_delete.push(*folds_cursor.start());
161 folds_cursor.next(&buffer);
162 }
163 }
164
165 fold_ixs_to_delete.sort_unstable();
166 fold_ixs_to_delete.dedup();
167
168 self.0.folds = {
169 let mut cursor = self.0.folds.cursor::<usize>();
170 let mut folds = SumTree::new();
171 for fold_ix in fold_ixs_to_delete {
172 folds.push_tree(cursor.slice(&fold_ix, Bias::Right, &buffer), &buffer);
173 cursor.next(&buffer);
174 }
175 folds.push_tree(cursor.suffix(&buffer), &buffer);
176 folds
177 };
178
179 consolidate_buffer_edits(&mut edits);
180 let edits = self.0.sync(buffer.clone(), edits);
181 let snapshot = FoldSnapshot {
182 transforms: self.0.transforms.lock().clone(),
183 folds: self.0.folds.clone(),
184 buffer_snapshot: buffer,
185 version: self.0.version.load(SeqCst),
186 };
187 (snapshot, edits)
188 }
189}
190
191pub struct FoldMap {
192 buffer: Mutex<BufferSnapshot>,
193 transforms: Mutex<SumTree<Transform>>,
194 folds: SumTree<Fold>,
195 version: AtomicUsize,
196}
197
198impl FoldMap {
199 pub fn new(buffer: BufferSnapshot) -> (Self, FoldSnapshot) {
200 let this = Self {
201 buffer: Mutex::new(buffer.clone()),
202 folds: Default::default(),
203 transforms: Mutex::new(SumTree::from_item(
204 Transform {
205 summary: TransformSummary {
206 input: buffer.text_summary(),
207 output: buffer.text_summary(),
208 },
209 output_text: None,
210 },
211 &(),
212 )),
213 version: Default::default(),
214 };
215
216 let snapshot = FoldSnapshot {
217 transforms: this.transforms.lock().clone(),
218 folds: this.folds.clone(),
219 buffer_snapshot: this.buffer.lock().clone(),
220 version: this.version.load(SeqCst),
221 };
222 (this, snapshot)
223 }
224
225 pub fn read(
226 &self,
227 buffer: BufferSnapshot,
228 edits: Vec<Edit<usize>>,
229 ) -> (FoldSnapshot, Vec<FoldEdit>) {
230 let edits = self.sync(buffer, edits);
231 self.check_invariants();
232 let snapshot = FoldSnapshot {
233 transforms: self.transforms.lock().clone(),
234 folds: self.folds.clone(),
235 buffer_snapshot: self.buffer.lock().clone(),
236 version: self.version.load(SeqCst),
237 };
238 (snapshot, edits)
239 }
240
241 pub fn write(
242 &mut self,
243 buffer: BufferSnapshot,
244 edits: Vec<Edit<usize>>,
245 ) -> (FoldMapWriter, FoldSnapshot, Vec<FoldEdit>) {
246 let (snapshot, edits) = self.read(buffer, edits);
247 (FoldMapWriter(self), snapshot, edits)
248 }
249
250 fn check_invariants(&self) {
251 if cfg!(test) {
252 assert_eq!(
253 self.transforms.lock().summary().input.bytes,
254 self.buffer.lock().len(),
255 "transform tree does not match buffer's length"
256 );
257 }
258 }
259
260 fn sync(
261 &self,
262 new_buffer: BufferSnapshot,
263 buffer_edits: Vec<text::Edit<usize>>,
264 ) -> Vec<FoldEdit> {
265 if buffer_edits.is_empty() {
266 let mut buffer = self.buffer.lock();
267 if buffer.parse_count() != new_buffer.parse_count()
268 || buffer.diagnostics_update_count() != new_buffer.diagnostics_update_count()
269 {
270 self.version.fetch_add(1, SeqCst);
271 }
272 *buffer = new_buffer;
273 Vec::new()
274 } else {
275 let mut buffer_edits_iter = buffer_edits.iter().cloned().peekable();
276
277 let mut new_transforms = SumTree::new();
278 let mut transforms = self.transforms.lock();
279 let mut cursor = transforms.cursor::<usize>();
280 cursor.seek(&0, Bias::Right, &());
281
282 while let Some(mut edit) = buffer_edits_iter.next() {
283 new_transforms.push_tree(cursor.slice(&edit.old.start, Bias::Left, &()), &());
284 edit.new.start -= edit.old.start - cursor.start();
285 edit.old.start = *cursor.start();
286
287 cursor.seek(&edit.old.end, Bias::Right, &());
288 cursor.next(&());
289
290 let mut delta = edit.new.len() as isize - edit.old.len() as isize;
291 loop {
292 edit.old.end = *cursor.start();
293
294 if let Some(next_edit) = buffer_edits_iter.peek() {
295 if next_edit.old.start > edit.old.end {
296 break;
297 }
298
299 let next_edit = buffer_edits_iter.next().unwrap();
300 delta += next_edit.new.len() as isize - next_edit.old.len() as isize;
301
302 if next_edit.old.end >= edit.old.end {
303 edit.old.end = next_edit.old.end;
304 cursor.seek(&edit.old.end, Bias::Right, &());
305 cursor.next(&());
306 }
307 } else {
308 break;
309 }
310 }
311
312 edit.new.end = ((edit.new.start + edit.old.len()) as isize + delta) as usize;
313
314 let anchor = new_buffer.anchor_before(edit.new.start);
315 let mut folds_cursor = self.folds.cursor::<Fold>();
316 folds_cursor.seek(&Fold(anchor..Anchor::max()), Bias::Left, &new_buffer);
317
318 let mut folds = iter::from_fn({
319 let buffer = &new_buffer;
320 move || {
321 let item = folds_cursor
322 .item()
323 .map(|f| f.0.start.to_offset(buffer)..f.0.end.to_offset(buffer));
324 folds_cursor.next(buffer);
325 item
326 }
327 })
328 .peekable();
329
330 while folds.peek().map_or(false, |fold| fold.start < edit.new.end) {
331 let mut fold = folds.next().unwrap();
332 let sum = new_transforms.summary();
333
334 assert!(fold.start >= sum.input.bytes);
335
336 while folds
337 .peek()
338 .map_or(false, |next_fold| next_fold.start <= fold.end)
339 {
340 let next_fold = folds.next().unwrap();
341 if next_fold.end > fold.end {
342 fold.end = next_fold.end;
343 }
344 }
345
346 if fold.start > sum.input.bytes {
347 let text_summary = new_buffer
348 .text_summary_for_range::<TextSummary, _>(sum.input.bytes..fold.start);
349 new_transforms.push(
350 Transform {
351 summary: TransformSummary {
352 output: text_summary.clone(),
353 input: text_summary,
354 },
355 output_text: None,
356 },
357 &(),
358 );
359 }
360
361 if fold.end > fold.start {
362 let output_text = "…";
363 let chars = output_text.chars().count() as u32;
364 let lines = Point::new(0, output_text.len() as u32);
365 let lines_utf16 =
366 PointUtf16::new(0, output_text.encode_utf16().count() as u32);
367 new_transforms.push(
368 Transform {
369 summary: TransformSummary {
370 output: TextSummary {
371 bytes: output_text.len(),
372 lines,
373 lines_utf16,
374 first_line_chars: chars,
375 last_line_chars: chars,
376 longest_row: 0,
377 longest_row_chars: chars,
378 },
379 input: new_buffer.text_summary_for_range(fold.start..fold.end),
380 },
381 output_text: Some(output_text),
382 },
383 &(),
384 );
385 }
386 }
387
388 let sum = new_transforms.summary();
389 if sum.input.bytes < edit.new.end {
390 let text_summary = new_buffer
391 .text_summary_for_range::<TextSummary, _>(sum.input.bytes..edit.new.end);
392 new_transforms.push(
393 Transform {
394 summary: TransformSummary {
395 output: text_summary.clone(),
396 input: text_summary,
397 },
398 output_text: None,
399 },
400 &(),
401 );
402 }
403 }
404
405 new_transforms.push_tree(cursor.suffix(&()), &());
406 if new_transforms.is_empty() {
407 let text_summary = new_buffer.text_summary();
408 new_transforms.push(
409 Transform {
410 summary: TransformSummary {
411 output: text_summary.clone(),
412 input: text_summary,
413 },
414 output_text: None,
415 },
416 &(),
417 );
418 }
419
420 drop(cursor);
421
422 let mut fold_edits = Vec::with_capacity(buffer_edits.len());
423 {
424 let mut old_transforms = transforms.cursor::<(usize, FoldOffset)>();
425 let mut new_transforms = new_transforms.cursor::<(usize, FoldOffset)>();
426
427 for mut edit in buffer_edits {
428 old_transforms.seek(&edit.old.start, Bias::Left, &());
429 if old_transforms.item().map_or(false, |t| t.is_fold()) {
430 edit.old.start = old_transforms.start().0;
431 }
432 let old_start =
433 old_transforms.start().1 .0 + (edit.old.start - old_transforms.start().0);
434
435 old_transforms.seek_forward(&edit.old.end, Bias::Right, &());
436 if old_transforms.item().map_or(false, |t| t.is_fold()) {
437 old_transforms.next(&());
438 edit.old.end = old_transforms.start().0;
439 }
440 let old_end =
441 old_transforms.start().1 .0 + (edit.old.end - old_transforms.start().0);
442
443 new_transforms.seek(&edit.new.start, Bias::Left, &());
444 if new_transforms.item().map_or(false, |t| t.is_fold()) {
445 edit.new.start = new_transforms.start().0;
446 }
447 let new_start =
448 new_transforms.start().1 .0 + (edit.new.start - new_transforms.start().0);
449
450 new_transforms.seek_forward(&edit.new.end, Bias::Right, &());
451 if new_transforms.item().map_or(false, |t| t.is_fold()) {
452 new_transforms.next(&());
453 edit.new.end = new_transforms.start().0;
454 }
455 let new_end =
456 new_transforms.start().1 .0 + (edit.new.end - new_transforms.start().0);
457
458 fold_edits.push(FoldEdit {
459 old: FoldOffset(old_start)..FoldOffset(old_end),
460 new: FoldOffset(new_start)..FoldOffset(new_end),
461 });
462 }
463
464 consolidate_fold_edits(&mut fold_edits);
465 }
466
467 *transforms = new_transforms;
468 *self.buffer.lock() = new_buffer;
469 self.version.fetch_add(1, SeqCst);
470 fold_edits
471 }
472 }
473}
474
475#[derive(Clone)]
476pub struct FoldSnapshot {
477 transforms: SumTree<Transform>,
478 folds: SumTree<Fold>,
479 buffer_snapshot: language::BufferSnapshot,
480 pub version: usize,
481}
482
483impl FoldSnapshot {
484 #[cfg(test)]
485 pub fn text(&self) -> String {
486 self.chunks(FoldOffset(0)..self.len(), None)
487 .map(|c| c.text)
488 .collect()
489 }
490
491 #[cfg(test)]
492 pub fn fold_count(&self) -> usize {
493 self.folds.items(&self.buffer_snapshot).len()
494 }
495
496 pub fn text_summary_for_range(&self, range: Range<FoldPoint>) -> TextSummary {
497 let mut summary = TextSummary::default();
498
499 let mut cursor = self.transforms.cursor::<(FoldPoint, Point)>();
500 cursor.seek(&range.start, Bias::Right, &());
501 if let Some(transform) = cursor.item() {
502 let start_in_transform = range.start.0 - cursor.start().0 .0;
503 let end_in_transform = cmp::min(range.end, cursor.end(&()).0).0 - cursor.start().0 .0;
504 if let Some(output_text) = transform.output_text {
505 summary = TextSummary::from(
506 &output_text
507 [start_in_transform.column as usize..end_in_transform.column as usize],
508 );
509 } else {
510 let buffer_start = cursor.start().1 + start_in_transform;
511 let buffer_end = cursor.start().1 + end_in_transform;
512 summary = self
513 .buffer_snapshot
514 .text_summary_for_range(buffer_start..buffer_end);
515 }
516 }
517
518 if range.end > cursor.end(&()).0 {
519 cursor.next(&());
520 summary += &cursor
521 .summary::<_, TransformSummary>(&range.end, Bias::Right, &())
522 .output;
523 if let Some(transform) = cursor.item() {
524 let end_in_transform = range.end.0 - cursor.start().0 .0;
525 if let Some(output_text) = transform.output_text {
526 summary += TextSummary::from(&output_text[..end_in_transform.column as usize]);
527 } else {
528 let buffer_start = cursor.start().1;
529 let buffer_end = cursor.start().1 + end_in_transform;
530 summary += self
531 .buffer_snapshot
532 .text_summary_for_range::<TextSummary, _>(buffer_start..buffer_end);
533 }
534 }
535 }
536
537 summary
538 }
539
540 pub fn len(&self) -> FoldOffset {
541 FoldOffset(self.transforms.summary().output.bytes)
542 }
543
544 #[cfg(test)]
545 pub fn line_len(&self, row: u32) -> u32 {
546 let line_start = FoldPoint::new(row, 0).to_offset(self).0;
547 let line_end = if row >= self.max_point().row() {
548 self.len().0
549 } else {
550 FoldPoint::new(row + 1, 0).to_offset(self).0 - 1
551 };
552 (line_end - line_start) as u32
553 }
554
555 pub fn buffer_rows(&self, start_row: u32) -> FoldBufferRows {
556 if start_row > self.transforms.summary().output.lines.row {
557 panic!("invalid display row {}", start_row);
558 }
559
560 let fold_point = FoldPoint::new(start_row, 0);
561 let mut cursor = self.transforms.cursor();
562 cursor.seek(&fold_point, Bias::Left, &());
563 FoldBufferRows { fold_point, cursor }
564 }
565
566 pub fn max_point(&self) -> FoldPoint {
567 FoldPoint(self.transforms.summary().output.lines)
568 }
569
570 #[cfg(test)]
571 pub fn longest_row(&self) -> u32 {
572 self.transforms.summary().output.longest_row
573 }
574
575 pub fn folds_in_range<'a, T>(
576 &'a self,
577 range: Range<T>,
578 ) -> impl Iterator<Item = &'a Range<Anchor>>
579 where
580 T: ToOffset,
581 {
582 let mut folds = intersecting_folds(&self.buffer_snapshot, &self.folds, range, false);
583 iter::from_fn(move || {
584 let item = folds.item().map(|f| &f.0);
585 folds.next(&self.buffer_snapshot);
586 item
587 })
588 }
589
590 pub fn intersects_fold<T>(&self, offset: T) -> bool
591 where
592 T: ToOffset,
593 {
594 let offset = offset.to_offset(&self.buffer_snapshot);
595 let mut cursor = self.transforms.cursor::<usize>();
596 cursor.seek(&offset, Bias::Right, &());
597 cursor.item().map_or(false, |t| t.output_text.is_some())
598 }
599
600 pub fn is_line_folded(&self, output_row: u32) -> bool {
601 let mut cursor = self.transforms.cursor::<FoldPoint>();
602 cursor.seek(&FoldPoint::new(output_row, 0), Bias::Right, &());
603 while let Some(transform) = cursor.item() {
604 if transform.output_text.is_some() {
605 return true;
606 }
607 if cursor.end(&()).row() == output_row {
608 cursor.next(&())
609 } else {
610 break;
611 }
612 }
613 false
614 }
615
616 pub fn chars_at(&self, start: FoldPoint) -> impl '_ + Iterator<Item = char> {
617 let start = start.to_offset(self);
618 self.chunks(start..self.len(), None)
619 .flat_map(|chunk| chunk.text.chars())
620 }
621
622 pub fn chunks<'a>(
623 &'a self,
624 range: Range<FoldOffset>,
625 theme: Option<&'a SyntaxTheme>,
626 ) -> FoldChunks<'a> {
627 let mut transform_cursor = self.transforms.cursor::<(FoldOffset, usize)>();
628
629 transform_cursor.seek(&range.end, Bias::Right, &());
630 let overshoot = range.end.0 - transform_cursor.start().0 .0;
631 let buffer_end = transform_cursor.start().1 + overshoot;
632
633 transform_cursor.seek(&range.start, Bias::Right, &());
634 let overshoot = range.start.0 - transform_cursor.start().0 .0;
635 let buffer_start = transform_cursor.start().1 + overshoot;
636
637 FoldChunks {
638 transform_cursor,
639 buffer_chunks: self.buffer_snapshot.chunks(buffer_start..buffer_end, theme),
640 buffer_chunk: None,
641 buffer_offset: buffer_start,
642 output_offset: range.start.0,
643 max_output_offset: range.end.0,
644 }
645 }
646
647 #[cfg(test)]
648 pub fn clip_offset(&self, offset: FoldOffset, bias: Bias) -> FoldOffset {
649 let mut cursor = self.transforms.cursor::<(FoldOffset, usize)>();
650 cursor.seek(&offset, Bias::Right, &());
651 if let Some(transform) = cursor.item() {
652 let transform_start = cursor.start().0 .0;
653 if transform.output_text.is_some() {
654 if offset.0 == transform_start || matches!(bias, Bias::Left) {
655 FoldOffset(transform_start)
656 } else {
657 FoldOffset(cursor.end(&()).0 .0)
658 }
659 } else {
660 let overshoot = offset.0 - transform_start;
661 let buffer_offset = cursor.start().1 + overshoot;
662 let clipped_buffer_offset = self.buffer_snapshot.clip_offset(buffer_offset, bias);
663 FoldOffset(
664 (offset.0 as isize + (clipped_buffer_offset as isize - buffer_offset as isize))
665 as usize,
666 )
667 }
668 } else {
669 FoldOffset(self.transforms.summary().output.bytes)
670 }
671 }
672
673 pub fn clip_point(&self, point: FoldPoint, bias: Bias) -> FoldPoint {
674 let mut cursor = self.transforms.cursor::<(FoldPoint, Point)>();
675 cursor.seek(&point, Bias::Right, &());
676 if let Some(transform) = cursor.item() {
677 let transform_start = cursor.start().0 .0;
678 if transform.output_text.is_some() {
679 if point.0 == transform_start || matches!(bias, Bias::Left) {
680 FoldPoint(transform_start)
681 } else {
682 FoldPoint(cursor.end(&()).0 .0)
683 }
684 } else {
685 let overshoot = point.0 - transform_start;
686 let buffer_position = cursor.start().1 + overshoot;
687 let clipped_buffer_position =
688 self.buffer_snapshot.clip_point(buffer_position, bias);
689 FoldPoint::new(
690 point.row(),
691 ((point.column() as i32) + clipped_buffer_position.column as i32
692 - buffer_position.column as i32) as u32,
693 )
694 }
695 } else {
696 FoldPoint(self.transforms.summary().output.lines)
697 }
698 }
699}
700
701fn intersecting_folds<'a, T>(
702 buffer: &'a text::BufferSnapshot,
703 folds: &'a SumTree<Fold>,
704 range: Range<T>,
705 inclusive: bool,
706) -> FilterCursor<'a, impl 'a + FnMut(&FoldSummary) -> bool, Fold, usize>
707where
708 T: ToOffset,
709{
710 let start = buffer.anchor_before(range.start.to_offset(buffer));
711 let end = buffer.anchor_after(range.end.to_offset(buffer));
712 folds.filter::<_, usize>(
713 move |summary| {
714 let start_cmp = start.cmp(&summary.max_end, buffer).unwrap();
715 let end_cmp = end.cmp(&summary.min_start, buffer).unwrap();
716
717 if inclusive {
718 start_cmp <= Ordering::Equal && end_cmp >= Ordering::Equal
719 } else {
720 start_cmp == Ordering::Less && end_cmp == Ordering::Greater
721 }
722 },
723 buffer,
724 )
725}
726
727fn consolidate_buffer_edits(edits: &mut Vec<text::Edit<usize>>) {
728 edits.sort_unstable_by(|a, b| {
729 a.old
730 .start
731 .cmp(&b.old.start)
732 .then_with(|| b.old.end.cmp(&a.old.end))
733 });
734
735 let mut i = 1;
736 while i < edits.len() {
737 let edit = edits[i].clone();
738 let prev_edit = &mut edits[i - 1];
739 if prev_edit.old.end >= edit.old.start {
740 prev_edit.old.end = prev_edit.old.end.max(edit.old.end);
741 prev_edit.new.start = prev_edit.new.start.min(edit.new.start);
742 prev_edit.new.end = prev_edit.new.end.max(edit.new.end);
743 edits.remove(i);
744 continue;
745 }
746 i += 1;
747 }
748}
749
750fn consolidate_fold_edits(edits: &mut Vec<FoldEdit>) {
751 edits.sort_unstable_by(|a, b| {
752 a.old
753 .start
754 .cmp(&b.old.start)
755 .then_with(|| b.old.end.cmp(&a.old.end))
756 });
757
758 let mut i = 1;
759 while i < edits.len() {
760 let edit = edits[i].clone();
761 let prev_edit = &mut edits[i - 1];
762 if prev_edit.old.end >= edit.old.start {
763 prev_edit.old.end = prev_edit.old.end.max(edit.old.end);
764 prev_edit.new.start = prev_edit.new.start.min(edit.new.start);
765 prev_edit.new.end = prev_edit.new.end.max(edit.new.end);
766 edits.remove(i);
767 continue;
768 }
769 i += 1;
770 }
771}
772
773#[derive(Clone, Debug, Default, Eq, PartialEq)]
774struct Transform {
775 summary: TransformSummary,
776 output_text: Option<&'static str>,
777}
778
779impl Transform {
780 fn is_fold(&self) -> bool {
781 self.output_text.is_some()
782 }
783}
784
785#[derive(Clone, Debug, Default, Eq, PartialEq)]
786struct TransformSummary {
787 output: TextSummary,
788 input: TextSummary,
789}
790
791impl sum_tree::Item for Transform {
792 type Summary = TransformSummary;
793
794 fn summary(&self) -> Self::Summary {
795 self.summary.clone()
796 }
797}
798
799impl sum_tree::Summary for TransformSummary {
800 type Context = ();
801
802 fn add_summary(&mut self, other: &Self, _: &()) {
803 self.input += &other.input;
804 self.output += &other.output;
805 }
806}
807
808#[derive(Clone, Debug)]
809struct Fold(Range<Anchor>);
810
811impl Default for Fold {
812 fn default() -> Self {
813 Self(Anchor::min()..Anchor::max())
814 }
815}
816
817impl sum_tree::Item for Fold {
818 type Summary = FoldSummary;
819
820 fn summary(&self) -> Self::Summary {
821 FoldSummary {
822 start: self.0.start.clone(),
823 end: self.0.end.clone(),
824 min_start: self.0.start.clone(),
825 max_end: self.0.end.clone(),
826 count: 1,
827 }
828 }
829}
830
831#[derive(Clone, Debug)]
832struct FoldSummary {
833 start: Anchor,
834 end: Anchor,
835 min_start: Anchor,
836 max_end: Anchor,
837 count: usize,
838}
839
840impl Default for FoldSummary {
841 fn default() -> Self {
842 Self {
843 start: Anchor::min(),
844 end: Anchor::max(),
845 min_start: Anchor::max(),
846 max_end: Anchor::min(),
847 count: 0,
848 }
849 }
850}
851
852impl sum_tree::Summary for FoldSummary {
853 type Context = text::BufferSnapshot;
854
855 fn add_summary(&mut self, other: &Self, buffer: &text::BufferSnapshot) {
856 if other.min_start.cmp(&self.min_start, buffer).unwrap() == Ordering::Less {
857 self.min_start = other.min_start.clone();
858 }
859 if other.max_end.cmp(&self.max_end, buffer).unwrap() == Ordering::Greater {
860 self.max_end = other.max_end.clone();
861 }
862
863 #[cfg(debug_assertions)]
864 {
865 let start_comparison = self.start.cmp(&other.start, buffer).unwrap();
866 assert!(start_comparison <= Ordering::Equal);
867 if start_comparison == Ordering::Equal {
868 assert!(self.end.cmp(&other.end, buffer).unwrap() >= Ordering::Equal);
869 }
870 }
871
872 self.start = other.start.clone();
873 self.end = other.end.clone();
874 self.count += other.count;
875 }
876}
877
878impl<'a> sum_tree::Dimension<'a, FoldSummary> for Fold {
879 fn add_summary(&mut self, summary: &'a FoldSummary, _: &text::BufferSnapshot) {
880 self.0.start = summary.start.clone();
881 self.0.end = summary.end.clone();
882 }
883}
884
885impl<'a> sum_tree::SeekTarget<'a, FoldSummary, Fold> for Fold {
886 fn cmp(&self, other: &Self, buffer: &text::BufferSnapshot) -> Ordering {
887 self.0.cmp(&other.0, buffer).unwrap()
888 }
889}
890
891impl<'a> sum_tree::Dimension<'a, FoldSummary> for usize {
892 fn add_summary(&mut self, summary: &'a FoldSummary, _: &text::BufferSnapshot) {
893 *self += summary.count;
894 }
895}
896
897pub struct FoldBufferRows<'a> {
898 cursor: Cursor<'a, Transform, (FoldPoint, Point)>,
899 fold_point: FoldPoint,
900}
901
902impl<'a> Iterator for FoldBufferRows<'a> {
903 type Item = u32;
904
905 fn next(&mut self) -> Option<Self::Item> {
906 while self.fold_point > self.cursor.end(&()).0 {
907 self.cursor.next(&());
908 if self.cursor.item().is_none() {
909 // TODO: Return a bool from next?
910 break;
911 }
912 }
913
914 if self.cursor.item().is_some() {
915 let overshoot = self.fold_point.0 - self.cursor.start().0 .0;
916 let buffer_point = self.cursor.start().1 + overshoot;
917 *self.fold_point.row_mut() += 1;
918 Some(buffer_point.row)
919 } else {
920 None
921 }
922 }
923}
924
925pub struct FoldChunks<'a> {
926 transform_cursor: Cursor<'a, Transform, (FoldOffset, usize)>,
927 buffer_chunks: language::BufferChunks<'a>,
928 buffer_chunk: Option<(usize, Chunk<'a>)>,
929 buffer_offset: usize,
930 output_offset: usize,
931 max_output_offset: usize,
932}
933
934impl<'a> Iterator for FoldChunks<'a> {
935 type Item = Chunk<'a>;
936
937 fn next(&mut self) -> Option<Self::Item> {
938 if self.output_offset >= self.max_output_offset {
939 return None;
940 }
941
942 let transform = if let Some(item) = self.transform_cursor.item() {
943 item
944 } else {
945 return None;
946 };
947
948 // If we're in a fold, then return the fold's display text and
949 // advance the transform and buffer cursors to the end of the fold.
950 if let Some(output_text) = transform.output_text {
951 self.buffer_chunk.take();
952 self.buffer_offset += transform.summary.input.bytes;
953 self.buffer_chunks.seek(self.buffer_offset);
954
955 while self.buffer_offset >= self.transform_cursor.end(&()).1
956 && self.transform_cursor.item().is_some()
957 {
958 self.transform_cursor.next(&());
959 }
960
961 self.output_offset += output_text.len();
962 return Some(Chunk {
963 text: output_text,
964 highlight_style: None,
965 diagnostic: None,
966 });
967 }
968
969 // Retrieve a chunk from the current location in the buffer.
970 if self.buffer_chunk.is_none() {
971 let chunk_offset = self.buffer_chunks.offset();
972 self.buffer_chunk = self.buffer_chunks.next().map(|chunk| (chunk_offset, chunk));
973 }
974
975 // Otherwise, take a chunk from the buffer's text.
976 if let Some((chunk_offset, mut chunk)) = self.buffer_chunk {
977 let offset_in_chunk = self.buffer_offset - chunk_offset;
978 chunk.text = &chunk.text[offset_in_chunk..];
979
980 // Truncate the chunk so that it ends at the next fold.
981 let region_end = self.transform_cursor.end(&()).1 - self.buffer_offset;
982 if chunk.text.len() >= region_end {
983 chunk.text = &chunk.text[0..region_end];
984 self.transform_cursor.next(&());
985 } else {
986 self.buffer_chunk.take();
987 }
988
989 self.buffer_offset += chunk.text.len();
990 self.output_offset += chunk.text.len();
991 return Some(chunk);
992 }
993
994 None
995 }
996}
997
998impl<'a> sum_tree::Dimension<'a, TransformSummary> for FoldPoint {
999 fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1000 self.0 += &summary.output.lines;
1001 }
1002}
1003
1004#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
1005pub struct FoldOffset(pub usize);
1006
1007impl FoldOffset {
1008 pub fn to_point(&self, snapshot: &FoldSnapshot) -> FoldPoint {
1009 let mut cursor = snapshot
1010 .transforms
1011 .cursor::<(FoldOffset, TransformSummary)>();
1012 cursor.seek(self, Bias::Right, &());
1013 let overshoot = if cursor.item().map_or(true, |t| t.is_fold()) {
1014 Point::new(0, (self.0 - cursor.start().0 .0) as u32)
1015 } else {
1016 let buffer_offset = cursor.start().1.input.bytes + self.0 - cursor.start().0 .0;
1017 let buffer_point = snapshot.buffer_snapshot.to_point(buffer_offset);
1018 buffer_point - cursor.start().1.input.lines
1019 };
1020 FoldPoint(cursor.start().1.output.lines + overshoot)
1021 }
1022}
1023
1024impl Sub for FoldOffset {
1025 type Output = Self;
1026
1027 fn sub(self, rhs: Self) -> Self::Output {
1028 Self(self.0 - rhs.0)
1029 }
1030}
1031
1032impl<'a> sum_tree::Dimension<'a, TransformSummary> for FoldOffset {
1033 fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1034 self.0 += &summary.output.bytes;
1035 }
1036}
1037
1038impl<'a> sum_tree::Dimension<'a, TransformSummary> for Point {
1039 fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1040 *self += &summary.input.lines;
1041 }
1042}
1043
1044impl<'a> sum_tree::Dimension<'a, TransformSummary> for usize {
1045 fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1046 *self += &summary.input.bytes;
1047 }
1048}
1049
1050pub type FoldEdit = Edit<FoldOffset>;
1051
1052#[cfg(test)]
1053mod tests {
1054 use super::*;
1055 use crate::ToPoint;
1056 use language::Buffer;
1057 use rand::prelude::*;
1058 use std::{env, mem};
1059 use text::RandomCharIter;
1060 use util::test::sample_text;
1061 use Bias::{Left, Right};
1062
1063 #[gpui::test]
1064 fn test_basic_folds(cx: &mut gpui::MutableAppContext) {
1065 let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(5, 6, 'a'), cx));
1066 let buffer_snapshot = buffer.read(cx).snapshot();
1067 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1068
1069 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1070 let (snapshot2, edits) = writer.fold(vec![
1071 Point::new(0, 2)..Point::new(2, 2),
1072 Point::new(2, 4)..Point::new(4, 1),
1073 ]);
1074 assert_eq!(snapshot2.text(), "aa…cc…eeeee");
1075 assert_eq!(
1076 edits,
1077 &[
1078 FoldEdit {
1079 old: FoldOffset(2)..FoldOffset(16),
1080 new: FoldOffset(2)..FoldOffset(5),
1081 },
1082 FoldEdit {
1083 old: FoldOffset(18)..FoldOffset(29),
1084 new: FoldOffset(7)..FoldOffset(10)
1085 },
1086 ]
1087 );
1088
1089 let (buffer_snapshot, edits) = buffer.update(cx, |buffer, cx| {
1090 let v0 = buffer.version();
1091 buffer.edit(
1092 vec![
1093 Point::new(0, 0)..Point::new(0, 1),
1094 Point::new(2, 3)..Point::new(2, 3),
1095 ],
1096 "123",
1097 cx,
1098 );
1099 (buffer.snapshot(), buffer.edits_since(&v0).collect())
1100 });
1101 let (snapshot3, edits) = map.read(buffer_snapshot.clone(), edits);
1102 assert_eq!(snapshot3.text(), "123a…c123c…eeeee");
1103 assert_eq!(
1104 edits,
1105 &[
1106 FoldEdit {
1107 old: FoldOffset(0)..FoldOffset(1),
1108 new: FoldOffset(0)..FoldOffset(3),
1109 },
1110 FoldEdit {
1111 old: FoldOffset(6)..FoldOffset(6),
1112 new: FoldOffset(8)..FoldOffset(11),
1113 },
1114 ]
1115 );
1116
1117 let (buffer_snapshot, edits) = buffer.update(cx, |buffer, cx| {
1118 let v0 = buffer.version();
1119 buffer.edit(vec![Point::new(2, 6)..Point::new(4, 3)], "456", cx);
1120 (buffer.snapshot(), buffer.edits_since(&v0).collect())
1121 });
1122 let (snapshot4, _) = map.read(buffer_snapshot.clone(), edits);
1123 assert_eq!(snapshot4.text(), "123a…c123456eee");
1124
1125 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1126 writer.unfold(Some(Point::new(0, 4)..Point::new(0, 5)));
1127 let (snapshot5, _) = map.read(buffer_snapshot.clone(), vec![]);
1128 assert_eq!(snapshot5.text(), "123aaaaa\nbbbbbb\nccc123456eee");
1129 }
1130
1131 #[gpui::test]
1132 fn test_adjacent_folds(cx: &mut gpui::MutableAppContext) {
1133 let buffer = cx.add_model(|cx| Buffer::new(0, "abcdefghijkl", cx));
1134 let buffer_snapshot = buffer.read(cx).snapshot();
1135
1136 {
1137 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1138
1139 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1140 writer.fold(vec![5..8]);
1141 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1142 assert_eq!(snapshot.text(), "abcde…ijkl");
1143
1144 // Create an fold adjacent to the start of the first fold.
1145 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1146 writer.fold(vec![0..1, 2..5]);
1147 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1148 assert_eq!(snapshot.text(), "…b…ijkl");
1149
1150 // Create an fold adjacent to the end of the first fold.
1151 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1152 writer.fold(vec![11..11, 8..10]);
1153 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1154 assert_eq!(snapshot.text(), "…b…kl");
1155 }
1156
1157 {
1158 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1159
1160 // Create two adjacent folds.
1161 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1162 writer.fold(vec![0..2, 2..5]);
1163 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1164 assert_eq!(snapshot.text(), "…fghijkl");
1165
1166 // Edit within one of the folds.
1167 let (buffer_snapshot, edits) = buffer.update(cx, |buffer, cx| {
1168 let v0 = buffer.version();
1169 buffer.edit(vec![0..1], "12345", cx);
1170 (buffer.snapshot(), buffer.edits_since(&v0).collect())
1171 });
1172 let (snapshot, _) = map.read(buffer_snapshot.clone(), edits);
1173 assert_eq!(snapshot.text(), "12345…fghijkl");
1174 }
1175 }
1176
1177 #[gpui::test]
1178 fn test_overlapping_folds(cx: &mut gpui::MutableAppContext) {
1179 let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(5, 6, 'a'), cx));
1180 let buffer_snapshot = buffer.read(cx).snapshot();
1181 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1182 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1183 writer.fold(vec![
1184 Point::new(0, 2)..Point::new(2, 2),
1185 Point::new(0, 4)..Point::new(1, 0),
1186 Point::new(1, 2)..Point::new(3, 2),
1187 Point::new(3, 1)..Point::new(4, 1),
1188 ]);
1189 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1190 assert_eq!(snapshot.text(), "aa…eeeee");
1191 }
1192
1193 #[gpui::test]
1194 fn test_merging_folds_via_edit(cx: &mut gpui::MutableAppContext) {
1195 let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(5, 6, 'a'), cx));
1196 let buffer_snapshot = buffer.read(cx).snapshot();
1197 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1198
1199 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1200 writer.fold(vec![
1201 Point::new(0, 2)..Point::new(2, 2),
1202 Point::new(3, 1)..Point::new(4, 1),
1203 ]);
1204 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1205 assert_eq!(snapshot.text(), "aa…cccc\nd…eeeee");
1206
1207 let (buffer_snapshot, edits) = buffer.update(cx, |buffer, cx| {
1208 let v0 = buffer.version();
1209 buffer.edit(Some(Point::new(2, 2)..Point::new(3, 1)), "", cx);
1210 (buffer.snapshot(), buffer.edits_since(&v0).collect())
1211 });
1212 let (snapshot, _) = map.read(buffer_snapshot.clone(), edits);
1213 assert_eq!(snapshot.text(), "aa…eeeee");
1214 }
1215
1216 #[gpui::test]
1217 fn test_folds_in_range(cx: &mut gpui::MutableAppContext) {
1218 let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(5, 6, 'a'), cx));
1219 let buffer_snapshot = buffer.read(cx).snapshot();
1220 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1221 let buffer = buffer.read(cx);
1222
1223 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1224 writer.fold(vec![
1225 Point::new(0, 2)..Point::new(2, 2),
1226 Point::new(0, 4)..Point::new(1, 0),
1227 Point::new(1, 2)..Point::new(3, 2),
1228 Point::new(3, 1)..Point::new(4, 1),
1229 ]);
1230 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1231 let fold_ranges = snapshot
1232 .folds_in_range(Point::new(1, 0)..Point::new(1, 3))
1233 .map(|fold| fold.start.to_point(buffer)..fold.end.to_point(buffer))
1234 .collect::<Vec<_>>();
1235 assert_eq!(
1236 fold_ranges,
1237 vec![
1238 Point::new(0, 2)..Point::new(2, 2),
1239 Point::new(1, 2)..Point::new(3, 2)
1240 ]
1241 );
1242 }
1243
1244 #[gpui::test(iterations = 100)]
1245 fn test_random_folds(cx: &mut gpui::MutableAppContext, mut rng: StdRng) {
1246 let operations = env::var("OPERATIONS")
1247 .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
1248 .unwrap_or(10);
1249
1250 let buffer = cx.add_model(|cx| {
1251 let len = rng.gen_range(0..10);
1252 let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
1253 Buffer::new(0, text, cx)
1254 });
1255 let buffer_snapshot = buffer.read(cx).snapshot();
1256 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1257
1258 let (mut initial_snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1259 let mut snapshot_edits = Vec::new();
1260
1261 for _ in 0..operations {
1262 log::info!("text: {:?}", buffer.read(cx).text());
1263 let buffer_edits = match rng.gen_range(0..=100) {
1264 0..=59 => {
1265 snapshot_edits.extend(map.randomly_mutate(&mut rng));
1266 vec![]
1267 }
1268 _ => buffer.update(cx, |buffer, cx| {
1269 let start_version = buffer.version.clone();
1270 let edit_count = rng.gen_range(1..=5);
1271 buffer.randomly_edit(&mut rng, edit_count, cx);
1272 let edits = buffer
1273 .edits_since::<Point>(&start_version)
1274 .collect::<Vec<_>>();
1275 log::info!("editing {:?}", edits);
1276 buffer.edits_since::<usize>(&start_version).collect()
1277 }),
1278 };
1279 let buffer_snapshot = buffer.read(cx).snapshot();
1280
1281 let (snapshot, edits) = map.read(buffer_snapshot.clone(), buffer_edits);
1282 snapshot_edits.push((snapshot.clone(), edits));
1283
1284 let mut expected_text: String = buffer_snapshot.text().to_string();
1285 let mut expected_buffer_rows = Vec::new();
1286 let mut next_row = buffer_snapshot.max_point().row;
1287 for fold_range in map.merged_fold_ranges().into_iter().rev() {
1288 let fold_start = buffer_snapshot.point_for_offset(fold_range.start).unwrap();
1289 let fold_end = buffer_snapshot.point_for_offset(fold_range.end).unwrap();
1290 expected_buffer_rows.extend((fold_end.row + 1..=next_row).rev());
1291 next_row = fold_start.row;
1292
1293 expected_text.replace_range(fold_range.start..fold_range.end, "…");
1294 }
1295 expected_buffer_rows.extend((0..=next_row).rev());
1296 expected_buffer_rows.reverse();
1297
1298 assert_eq!(snapshot.text(), expected_text);
1299
1300 for (output_row, line) in expected_text.lines().enumerate() {
1301 let line_len = snapshot.line_len(output_row as u32);
1302 assert_eq!(line_len, line.len() as u32);
1303 }
1304
1305 let longest_row = snapshot.longest_row();
1306 let longest_char_column = expected_text
1307 .split('\n')
1308 .nth(longest_row as usize)
1309 .unwrap()
1310 .chars()
1311 .count();
1312 let mut fold_point = FoldPoint::new(0, 0);
1313 let mut fold_offset = FoldOffset(0);
1314 let mut char_column = 0;
1315 for c in expected_text.chars() {
1316 let buffer_point = fold_point.to_buffer_point(&snapshot);
1317 let buffer_offset = buffer_point.to_offset(&buffer_snapshot);
1318 assert_eq!(
1319 buffer_point.to_fold_point(&snapshot, Right),
1320 fold_point,
1321 "{:?} -> fold point",
1322 buffer_point,
1323 );
1324 assert_eq!(
1325 fold_point.to_buffer_offset(&snapshot),
1326 buffer_offset,
1327 "fold_point.to_buffer_offset({:?})",
1328 fold_point,
1329 );
1330 assert_eq!(
1331 fold_point.to_offset(&snapshot),
1332 fold_offset,
1333 "fold_point.to_offset({:?})",
1334 fold_point,
1335 );
1336
1337 if c == '\n' {
1338 *fold_point.row_mut() += 1;
1339 *fold_point.column_mut() = 0;
1340 char_column = 0;
1341 } else {
1342 *fold_point.column_mut() += c.len_utf8() as u32;
1343 char_column += 1;
1344 }
1345 fold_offset.0 += c.len_utf8();
1346 if char_column > longest_char_column {
1347 panic!(
1348 "invalid longest row {:?} (chars {}), found row {:?} (chars: {})",
1349 longest_row,
1350 longest_char_column,
1351 fold_point.row(),
1352 char_column
1353 );
1354 }
1355 }
1356
1357 for _ in 0..5 {
1358 let mut start = snapshot
1359 .clip_offset(FoldOffset(rng.gen_range(0..=snapshot.len().0)), Bias::Left);
1360 let mut end = snapshot
1361 .clip_offset(FoldOffset(rng.gen_range(0..=snapshot.len().0)), Bias::Right);
1362 if start > end {
1363 mem::swap(&mut start, &mut end);
1364 }
1365
1366 let text = &expected_text[start.0..end.0];
1367 log::info!("slicing {:?}..{:?} (text: {:?})", start, end, text);
1368 assert_eq!(
1369 snapshot
1370 .chunks(start..end, None)
1371 .map(|c| c.text)
1372 .collect::<String>(),
1373 text,
1374 );
1375 }
1376
1377 for (idx, buffer_row) in expected_buffer_rows.iter().enumerate() {
1378 let fold_row = Point::new(*buffer_row, 0)
1379 .to_fold_point(&snapshot, Right)
1380 .row();
1381 assert_eq!(
1382 snapshot.buffer_rows(fold_row).collect::<Vec<_>>(),
1383 expected_buffer_rows[idx..],
1384 );
1385 }
1386
1387 for fold_range in map.merged_fold_ranges() {
1388 let fold_point = fold_range
1389 .start
1390 .to_point(&buffer_snapshot)
1391 .to_fold_point(&snapshot, Right);
1392 assert!(snapshot.is_line_folded(fold_point.row()));
1393 }
1394
1395 for _ in 0..5 {
1396 let end =
1397 buffer_snapshot.clip_offset(rng.gen_range(0..=buffer_snapshot.len()), Right);
1398 let start = buffer_snapshot.clip_offset(rng.gen_range(0..=end), Left);
1399 let expected_folds = map
1400 .folds
1401 .items(&buffer_snapshot)
1402 .into_iter()
1403 .filter(|fold| {
1404 let start = buffer_snapshot.anchor_before(start);
1405 let end = buffer_snapshot.anchor_after(end);
1406 start.cmp(&fold.0.end, &buffer_snapshot).unwrap() == Ordering::Less
1407 && end.cmp(&fold.0.start, &buffer_snapshot).unwrap()
1408 == Ordering::Greater
1409 })
1410 .map(|fold| fold.0)
1411 .collect::<Vec<_>>();
1412
1413 assert_eq!(
1414 snapshot
1415 .folds_in_range(start..end)
1416 .cloned()
1417 .collect::<Vec<_>>(),
1418 expected_folds
1419 );
1420 }
1421
1422 let text = snapshot.text();
1423 for _ in 0..5 {
1424 let start_row = rng.gen_range(0..=snapshot.max_point().row());
1425 let start_column = rng.gen_range(0..=snapshot.line_len(start_row));
1426 let end_row = rng.gen_range(0..=snapshot.max_point().row());
1427 let end_column = rng.gen_range(0..=snapshot.line_len(end_row));
1428 let mut start =
1429 snapshot.clip_point(FoldPoint::new(start_row, start_column), Bias::Left);
1430 let mut end = snapshot.clip_point(FoldPoint::new(end_row, end_column), Bias::Right);
1431 if start > end {
1432 mem::swap(&mut start, &mut end);
1433 }
1434
1435 let lines = start..end;
1436 let bytes = start.to_offset(&snapshot)..end.to_offset(&snapshot);
1437 assert_eq!(
1438 snapshot.text_summary_for_range(lines),
1439 TextSummary::from(&text[bytes.start.0..bytes.end.0])
1440 )
1441 }
1442
1443 let mut text = initial_snapshot.text();
1444 for (snapshot, edits) in snapshot_edits.drain(..) {
1445 let new_text = snapshot.text();
1446 for edit in edits {
1447 let old_bytes = edit.new.start.0..edit.new.start.0 + edit.old_len().0;
1448 let new_bytes = edit.new.start.0..edit.new.end.0;
1449 text.replace_range(old_bytes, &new_text[new_bytes]);
1450 }
1451
1452 assert_eq!(text, new_text);
1453 initial_snapshot = snapshot;
1454 }
1455 }
1456 }
1457
1458 #[gpui::test]
1459 fn test_buffer_rows(cx: &mut gpui::MutableAppContext) {
1460 let text = sample_text(6, 6, 'a') + "\n";
1461 let buffer = cx.add_model(|cx| Buffer::new(0, text, cx));
1462
1463 let buffer_snapshot = buffer.read(cx).snapshot();
1464 let mut map = FoldMap::new(buffer_snapshot.clone()).0;
1465
1466 let (mut writer, _, _) = map.write(buffer_snapshot.clone(), vec![]);
1467 writer.fold(vec![
1468 Point::new(0, 2)..Point::new(2, 2),
1469 Point::new(3, 1)..Point::new(4, 1),
1470 ]);
1471
1472 let (snapshot, _) = map.read(buffer_snapshot.clone(), vec![]);
1473 assert_eq!(snapshot.text(), "aa…cccc\nd…eeeee\nffffff\n");
1474 assert_eq!(snapshot.buffer_rows(0).collect::<Vec<_>>(), [0, 3, 5, 6]);
1475 assert_eq!(snapshot.buffer_rows(3).collect::<Vec<_>>(), [6]);
1476 }
1477
1478 impl FoldMap {
1479 fn merged_fold_ranges(&self) -> Vec<Range<usize>> {
1480 let buffer = self.buffer.lock().clone();
1481 let mut folds = self.folds.items(&buffer);
1482 // Ensure sorting doesn't change how folds get merged and displayed.
1483 folds.sort_by(|a, b| a.0.cmp(&b.0, &buffer).unwrap());
1484 let mut fold_ranges = folds
1485 .iter()
1486 .map(|fold| fold.0.start.to_offset(&buffer)..fold.0.end.to_offset(&buffer))
1487 .peekable();
1488
1489 let mut merged_ranges = Vec::new();
1490 while let Some(mut fold_range) = fold_ranges.next() {
1491 while let Some(next_range) = fold_ranges.peek() {
1492 if fold_range.end >= next_range.start {
1493 if next_range.end > fold_range.end {
1494 fold_range.end = next_range.end;
1495 }
1496 fold_ranges.next();
1497 } else {
1498 break;
1499 }
1500 }
1501 if fold_range.end > fold_range.start {
1502 merged_ranges.push(fold_range);
1503 }
1504 }
1505 merged_ranges
1506 }
1507
1508 pub fn randomly_mutate(
1509 &mut self,
1510 rng: &mut impl Rng,
1511 ) -> Vec<(FoldSnapshot, Vec<FoldEdit>)> {
1512 let mut snapshot_edits = Vec::new();
1513 match rng.gen_range(0..=100) {
1514 0..=39 if !self.folds.is_empty() => {
1515 let buffer = self.buffer.lock().clone();
1516 let mut to_unfold = Vec::new();
1517 for _ in 0..rng.gen_range(1..=3) {
1518 let end = buffer.clip_offset(rng.gen_range(0..=buffer.len()), Right);
1519 let start = buffer.clip_offset(rng.gen_range(0..=end), Left);
1520 to_unfold.push(start..end);
1521 }
1522 log::info!("unfolding {:?}", to_unfold);
1523 let (mut writer, snapshot, edits) = self.write(buffer, vec![]);
1524 snapshot_edits.push((snapshot, edits));
1525 let (snapshot, edits) = writer.fold(to_unfold);
1526 snapshot_edits.push((snapshot, edits));
1527 }
1528 _ => {
1529 let buffer = self.buffer.lock().clone();
1530 let mut to_fold = Vec::new();
1531 for _ in 0..rng.gen_range(1..=2) {
1532 let end = buffer.clip_offset(rng.gen_range(0..=buffer.len()), Right);
1533 let start = buffer.clip_offset(rng.gen_range(0..=end), Left);
1534 to_fold.push(start..end);
1535 }
1536 log::info!("folding {:?}", to_fold);
1537 let (mut writer, snapshot, edits) = self.write(buffer, vec![]);
1538 snapshot_edits.push((snapshot, edits));
1539 let (snapshot, edits) = writer.fold(to_fold);
1540 snapshot_edits.push((snapshot, edits));
1541 }
1542 }
1543 snapshot_edits
1544 }
1545 }
1546}